How to display data bottom of each column in component using ADF

Scenario : To display sum of data in a specific column at the bottom table component , For eg : Display sum of salaries of all the employees in <af:table> component, corresponding to 'Salary' column in <af:table> component

Resolution :

Include <f:facet name="footer">Determine Sum of salaries </f:facet> in <af:column> component.